Some diseases, such as Gitelman's syndrome, Bartter's syndrome, and primary hyperaldosteronism (Conn's syndrome), may bear some similar clinical and laboratory findings. Their treatment modalities being different from one another, the need for a scrupulous diagnostic evaluation arises as far as clinical practice is concerned. In this report, we present a patient with Conn's syndrome who was initially considered to have Gitelman's syndrome due to displaying a few overlapping features of both diseases. We also give an account of the hardships encountered during the diagnostic evaluation.